1. Field of Invention
The present invention relates to an optical element, an illuminator and a projection display device having the optical element.
2. Description of Related Art
It is advantageous to provide display devices that are large and that have high resolution. Projection display devices, such as liquid crystal projectors and digital mirror devices (DMDs), can easily achieve a large-screen display.
Among them, single-panel projection display devices, as disclosed in JP-A-2000-56410, can be advantageous because of their high throughput and simple structure, in which LED light sources of R (red), G (green), and B (blue), arranged around a dichroic prism, are lit on by time division and color light emitted from each light source is modulated with a light valve to be composed on a screen.